A202983 Number of nX3 0..2 arrays with every nonzero element less than or equal to some NW, E or S neighbor

1, 63, 1233, 16854, 239196, 3557168, 52328419, 764541713, 11194473148, 164061008324, 2403403907914, 35204470177631, 515704944067269, 7554581118847553, 110665921163215772, 1621126629146201847

Offset

1,2

Comments

Column 3 of A202988

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 27*a(n-1) -271*a(n-2) +1899*a(n-3) -11048*a(n-4) +44346*a(n-5) -113218*a(n-6) +201165*a(n-7) -291398*a(n-8) +360023*a(n-9) -334000*a(n-10) +199528*a(n-11) -66264*a(n-12) +9212*a(n-13)

Example

Some solutions for n=4
..1..1..0....0..0..0....0..1..0....2..2..2....2..2..2....0..2..1....0..1..1
..2..2..0....2..1..0....2..1..1....2..2..2....0..2..2....2..2..2....1..1..1
..0..2..0....2..2..0....2..2..0....1..0..1....0..1..2....2..2..2....0..1..1
..2..2..2....1..1..2....0..1..0....1..1..0....0..0..0....1..1..1....0..1..1

Crossrefs

Sequence in context: A183076 A230660 A132465 * A107319 A243214 A341569

Adjacent sequences: A202980 A202981 A202982 * A202984 A202985 A202986

Keyword

nonn

Author

R. H. Hardin Dec 26 2011

Status

approved